Sign language.

Dinner hour, and I sit down to the table with my wife and three small children, ready to talk turkey. Today it is my youngest son's turn for grace, and he starts us off with the sign of the cross. He has a unique take on this act, as in so many other aspects of his life: not unlike a third-base coach, he makes a flurry of motions, touching forehead, belly, shoulders, nose, temples, ears, and (finally) tongue, all the while chanting, at a terrific pace, "Father, Son, Spirit Holy."

As usual, he sends his family into stitches, and after a while we bring him around to a slightly more orthodox sign of the cross, but as his mother and sister and brother recover from the giggles and set to work eating their meals, his father's mind, as usual, rambles. Whence came this unusual motion of the hand and this incantation? Why do we mark moments great and small, holy and horrendous, with this gentle handmade echo of the crucifix? Father, Son, Holy Spirit, I whisper in moments of joy and fear, prayer and penitence, before a meal, during the Mass, after a death. I make the sign of the cross in wonder. I make it in gratitude. I make it in desperate prayer. I make it before meals, during Masses, after funerals, after Baptisms. I make it in awe and epiphany and tragedy.

I do it all the time, and I am by no means alone; no other simple physical gesture is so widespread among Catholics. More than sinking to our knees, more than folding our hands together in prayer, more than bowing our heads under blessings, it is the making of the sign of the cross with our hands that marks us as Catholics--as men and women (and small children) who believe in the risen Christ, the God and man who died on a wooden crucifix on the Hill of Skulls, long centuries ago.

Scholars trace the practice as far back as the, year 110 A.D., by which time it was already established as a common gesture among Christians. "Its format is a simple geometry," says the Congregation of Holy Cross theologian Father Jeffrey Sobosan "It traces out a cross in the sequence of four points touched: head to chest, shoulder to shoulder. The early Christians thought it was the way Jesus died, far more than the way he lived prior to his arrest, that constituted the saving act whereby he pleased God." So those early Christian cults honored, in a simple physical gesture, the geometric shape on which Christ gave his life for US.

It is a small miracle, perhaps, that this gesture has persisted unchanged throughout many nations and centuries, but miracles are not unusual, are they? Such a simple act, our hands cutting the air like the wings of birds, fingers alighting gently on our bodies in memory of the body broken for us.

"Father," we say, touching our heads, the seats of our cerebrations, and we think of the Maker, that vast incomprehensible coherence stitching everything together, and

"Son," touching our hearts, and feeling the ache and exhaustion of the Father's Son, the God-made-man, the gaunt, dusty, tireless fellow who walked and talked endlessly, who knew what would happen to him, who accepted it with amazing grace, who died screaming that we might live past death, and

"Holy," touching the left shoulder, on which we carry hope, and

"Spirit," touching the right shoulder, on which we carry love, and the gesture is done, hanging in the air like a memory, its line traced on my body as if printed there by the thousands of times my hand has marked it.

Simple, powerful, poignant, the sign of the cross is a mnemonic device like the Mass, in which we sit down to table with each other and remember the Last Supper, or a Baptism, where we remember John the Baptist's brawny arm pouring some of the Jordan River over Christ. So we remember the central miracle and paradox of the faith that binds us each to each: that we believe, against all evidence and sense, in life and love and light, in the victory of those things over death and evil and darkness. Such a ferocious and brave notion, to be hinted at by such a simple motion, and the gesture itself lasting perhaps all of four seconds--if you touch all the bases and don't rush.

But simple as the sign of the cross is, it carries a brave weight: it names the Trinity, celebrates the creator, and brings home all the power of faith to the brush of fingers on skin and bone and belly. So do we, sometimes well and sometimes ill, labor to bring home our belief in God's love to the stuff of our daily lives, the skin and bone of this world--and the sign of the cross helps us to remember that in God we have a companion on the road.

By Brian Doyle, editor of Portland Magazine at the University of Portland, in Oregon. He and his father Jim Doyle are the authors of Two Voices, a collection of essays.